/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.pinot.hadoop.io;

import java.io.IOException;
import java.util.Map;
import java.util.Set;
import org.apache.hadoop.conf.Configuration;


/**
 * The FieldExtractor extracts fields from the records.
 * @param <T> Type of the record
 */
public interface FieldExtractor<T> {

  /**
   * Initializes the FieldExtractor.
   */
  void init(Configuration conf, Set<String> fields);

  /**
   * Extracts the fields from the given record.
   */
  Map<String, Object> extractFields(T record)
      throws IOException;
}
